1. Field of the Invention
The present invention relates to a process for the manufacture of hydrogen sulfide by reacting sulfur with hydrogen gas.
2. Description of the Prior Art
Processes for the manufacture of hydrogen sulfide are well known in which sulfur and hydrogen are reacted in a gas phase. These conventional processes, however, are disadvantageous in that upon reaction between sulfur and hydrogen, the temperature of the reaction system increases considerably as a result of reaction heat, thus requiring control of the temperature of the reactor.
A well-known countermeasure for obviating the disadvantage was to use hydrogen in excess amounts and sulfur in smaller amounts in order to restrict the amount of reaction therebetween to some extent to reduce the increase in the temperature of the reaction system. However, this method is unsatisfactory because conversion rate of hydrogen is low, for example, as low as 10% in terms of the concentration of hydrogen sulfide produced, which means the efficiency of manufacture of hydrogen sulfide is low. Furthermore, the use of large amount of hydrogen results in that not only the size of production apparatus to be used per unit amount of hydrogen sulfide produced becomes large but also large installment is needed for recycling large amounts of hydrogen gas and running accompanied absorption and regeneration steps. These inevitably lead to the use of large, expensive manufacture apparatus.
Further approach to improve the above-described conventional process, was a process in which at least two gas phase reaction rooms which are communicated with each other. Each room is equipped at the inlet of the reaction room with a sulfur inlet room for introducing and gasifying sulfur hydrogen gas heated to a temperature sufficient for gasify sulfur is introduced through the gas phase reaction rooms in series while supplying sulfur in each of the sulfur inlet rooms separately to perform reaction between sulfur and hydrogen as described in Japanese Patent Publication (Kokoku) No. 46-5572 published Feb. 12, 1971.
The above-described process is still disadvantageous from economical viewpoint in that only 1 mol % of S.sub.8 (sulfur vapor) can be reacted in order to prevent increase in temperature above 100.degree. C. in a single step and as a result many steps are required for obtaining hydrogen sulfide in high concentration.